944 Clutch Problem?

Help! Was cruising in my '84 944 and depressed the clutch pedal, shifted up. The pedal returned about halfway.... Depressed it again to upshift and the pedal STUCK TO THE FLOOR. With the edge of my dress shoe I was able to hook under the pedal and pull it back up the full length of travel. This was 2 days ago - has been working fine since. What happened? Major problem coming on? Help